Image blocking teleconferencing eye contact terminal

ABSTRACT

The present invention enables eye contact between conferees during a teleconference using a terminal equipped with a beamsplitter for reflecting an image of a video display so that only the reflection and not a direct view of the display is seen by the conferee. The camera is positioned behind the viewing side of the beamsplitter to capture the conferee&#39;s image through the beamsplitter. The direct view of the display is blocked by an image blocking film applied between the beamsplitter and the display. Blocking the direct view of the video display greatly improves teleconferencing by eliminating the distraction of simultaneously viewing both the video display and the reflection of the display.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention concerns the area of teleconferencing and, morespecifically, an improved video teleconferencing device that permits eyecontact.

2. Description of Related Art

A primary concern in video-teleconferencing ergonomics is a lack of eyecontact between conferees. Eye contact is not possible with commonterminal configurations, because the camera is placed at the perimeterof the display that images a distant conferee, so that the camera doesnot interfere with a local conferee's viewing of the display. With thisconfiguration the conferees fail to look directly into the camera, whichresults in the appearance of the conferees looking away and appearingdisinterested in the conversation.

Although numerous technologies have been proposed to correct the eyecontact problem, many of these technologies suffer from poor imagecapture quality, poor image display quality, excessive expense, orunacceptably increased terminal bulk. One commonly used component in eyecontact systems is a beamsplitter. A beamsplitter is a semireflectivetransparent panel sometimes called a one way mirror or a semisilveredmirror. Although even a plain sheet of transparent material such asglass can be employed, it is more common to apply coatings to atransparent substrate to increase its reflectivity.

A common beamsplitter eye contact arrangement consists of a beamsplitterthat is mounted in front of a display oriented at about 45 degrees tothe display surface. The conferee using the terminal looks through thebeamsplitter to view the display. A camera is disposed in front of thebeamsplitter and captures an image of the conferee reflected in thesemireflective beamsplitter. This technology has a number of drawbacks.First, the 45-degree angle of the beamsplitter placed in front of thedisplay necessarily increases the bulk of the display. Second, if thebeamsplitter is illuminated by ambient light, the quality of the imagecaptured by the camera may be seriously degraded. This problem may beavoided by a hood of an opaque material extending from the display tothe edge of the beamsplitter so that ambient light does not degrade thereflected image. However, an opaque hood makes the beamsplitter appeareven more intrusive with the angled beamsplitter forming a visiblebarrier in front of the display surface. Whether the display is acomputer desktop monitor or a big screen television, the awkwardness ofthe protruding beamsplitter and camera remain an inefficient use ofspace.

U.S. Pat. No. 5,117,285 to Smoot attempted to reduce the bulk of thistype of terminal by applying polarizers to the display and camera, sothat the beamsplitter can be angled more acutely, approximately 30degrees, without having light from the display interfere with thereflection of the conferee. A drawback to this arrangement is theinherent loss of light caused by the polarizer which further reduces thedisplay image brightness, which has already been reduced by thebeamsplitter. Even though this technology reduces the angle of thebeamsplitter, it still adds considerable bulk to the terminal and atransparent barrier still remains in front of the display. Also,terminal bulk is further increased by the camera placement, which mustprotrude far from the display to capture the reflection of the confereein the 30-degree angled beamsplitter. This becomes a nuisance withdesktop conferencing, because the camera is positioned in the conferee'swork space where a keyboard is usually placed.

Another eye contact beamsplitter arrangement resolves this protrudingcamera problem by mounting it behind the beamsplitter. In thisarrangement, the display is reflected by the beamsplitter for viewing bythe conferee. The light of the reflection conceals the camera behind thebeamsplitter. The camera thus captures the image of the conferee throughthe beamsplitter. If a flat panel display is used or if a CRT display ismounted in a desk's surface and aimed upward, the bulk of this systemcan be reduced substantially.

However, even with these improvements this arrangement suffers from anadditional significant problem: namely the conferee can simultaneouslyobserve the displayed image both in two ways, either by directly viewingthe display or by viewing the reflection of the display on thebeamsplitter. That is, as the conferee looks at the reflected image, itis easy to glance at an angle and directly view the display below thebeamsplitter. The dual visible images in this arrangement is a severedistraction, as the conferee's attention is divided between the light oftwo images. If the conferee gazes directly at the display (as opposed tothe reflection of the display), eye contact will be disrupted becausethe camera will capture an image of the conferee that appears not tolook at the face of the remote conferee.

Prior Art Beamsplitter Arrangements

FIG. 1 illustrates a prior art eye contact beamsplitter arrangement inwhich the image of a conferee is captured by a camera 4 by means of areflection in a beamsplitter 6. At the same time the conferee's image iscaptured, that conferee is able to look through the beamsplitter 6 toview a display 2. A hood 8, usually covered with an opaque material, istypically included to shield the beamsplitter 6 from ambient light. Thedrawbacks to this arrangement include the increased bulk of the terminal(although a flat panel will minimize this problem), the addition of atransparent barrier in front of the display which affects viewing thedisplay surface, the appearance of the display being recessed far intothe terminal creating a tunnel effect and, lastly, the awkwardpositioning of the camera 4 which intrudes into the conferee's workspace.

FIG. 2 is a prior art eye contact beamsplitter arrangement that attemptsto reduce the protrusion of the beamsplitter 6 by adding a polarizer 9.Here when properly configured with a second polarizer 11 on the camera4, the camera 4 can be aimed more directly toward the display 2 withoutpicking up the image on the display 2 through the beamsplitter. Despitesome reduction in the angle of the beamsplitter 6, the unit stillsuffers from excessive bulk, a transparent barrier between the confereeand the viewing surface of the display 2. Also, the camera 4 protrudesawkwardly from the terminal on a stand 12, invading the conferee's workspace.

FIG. 3 presents a beamsplitter arrangement in which the conferee viewsthe reflection of the display 2 by the beamsplitter 6. The camera 4 issubstantially concealed from view behind the beamsplitter 6 and is aimedthrough the beamsplitter 6 to directly capture the image of theconferee. As is illustrated, the significant drawback of thisarrangement is the fact that the light from the display 2 is visible tothe conferee simultaneously at the display 2 and as the reflection ofthe display 2 in the beamsplitter 6 by the conferee. These two visibleimages compete for the conferee's attention and add distraction whileconferencing, thereby reducing the quality of the conferencingexperience.

OBJECTS AND SUMMARY OF THE INVENTION

It is an object of the present invention to provide a teleconferencingbeamsplitter eye contact terminal with an image blocking film, so thatlight from the display source is concealed from the point of view of theconferee while simultaneously allowing a reflection of the display on abeamsplitter that is viewed by the conferee.

It is a further object of this invention to provide an eye contactterminal consisting of at least a camera and display configured in asingle unit.

It is a further object of this invention to provide an eye contactterminal built integrally with various types of consumer electronicdevices.

It is a further object of this invention to provide a eye contactterminal that has separate components for ease of upgrading.

It is a further object of this invention to enable convenientpositioning of the beamsplitter in relation to the display.

It is a further object of this invention to provide a teleconferencingbeamsplitter that is shielded from ambient light.

Lastly, it is an object of the present invention to use an imageblocking film to enable a camera to capture a reflection of a confereein a beamsplitter aimed directly toward the display.

The present invention enables eye contact between conferees during aconference with a terminal that utilizes a beamsplitter that reflectsthe image of the display in such a way that only the reflection and notthe display is seen by the conferee. The camera is positioned behind theviewing side of the beamsplitter in order to capture the conferee'simage through the beamsplitter. To block unwanted light directly fromthe display, an image blocking film is applied between the beamsplitterand the display so that light from the display is concealed from theconferees's direct view. This concealment greatly improves thisteleconferencing beamsplitter arrangement by eliminating the distractionof viewing both the display and the display reflection. Also, the camerais positioned behind the beamsplitter, so it does not disturb the workspace of the conferee, thereby greatly improving this beamsplitterarrangement's practicality for desktop and other types of conferencing.

BRIEF DESCRIPTION OF THE DRAWINGS

The objects and features of the present invention, which are believed tobe novel, are set forth with particularity in the appended claims. Thepresent invention, both as to its organization and manner of operation,together with further objects and advantages, may best be understood byreference to the following description, taken in connection with theaccompanying drawings.

FIG. 1 illustrates a prior art beamsplitter arrangement in which theconferee views the display through a beamsplitter;

FIG. 2 illustrates a prior art beamsplitter arrangement that isconfigured with polarizers to reduce the angle of the beamsplitter fromthe display;

FIG. 3 illustrates a prior art beamsplitter arrangement in which theconferee is intended to view only the reflection of the display yet canstill see light emanating directly from the display;

FIG. 4 illustrates the present invention in which image blocking film isused to conceal the display from direct viewing by the conferee;

FIG. 5 illustrates an embodiment of the present invention that concealsview of the display of light from all four sides;

FIG. 6 illustrates the present invention configured with the displaylaying flat and aimed upwards;

FIG. 7 illustrates the present invention configured with the displayaimed downward;

FIG. 8 illustrates the present invention configured as a display of alaptop computer;

FIG. 9 illustrates the present invention configured as a separate unitthat can be added to a display;

FIG. 10 illustrates a display with modifications to assist in thepositioning of the reflection for desired viewing;

FIG. 11 illustrates an extension arm system which permits numerouspositioning options of the beamsplitter in relation to the display;

FIG. 12 illustrates opaque material placed behind the beamsplitter;

FIG. 13 illustrates a beamsplitter with image blocking film appliedbehind the viewing side, so that ambient light is substantially reduced;

FIG. 14 illustrates sound from a speaker bouncing off the beamsplitter;

FIG. 15 illustrates a beamsplitter that is bowed, so that a compressedimage is expanded when reflected;

FIG. 16 illustrates image blocking film angled in relation to thedisplay to prevent reflections back onto the image blocking film; and

FIG. 17 illustrates an alternative beamsplitter arrangement wherein theimage blocking film is used to prevent light from the display from beingcaptured by the camera.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The following description is provided to enable any person skilled inthe art to make and use the invention and sets forth the best modescontemplated by the inventors for carrying out their invention. Variousmodifications, however, will remain readily apparent to those skilled inthe art, since the generic principles of the present invention have beendefined herein specifically to provide an improved beamsplitter-basedteleconferencing device that uses image blocking film to eliminatedistracting images.

Image Blocking Teleconferencing Eye Contact Terminal

An eye contact beamsplitter arrangement has been invented to overcomethe problem of a conferee simultaneously viewing both the display andits reflection. An image blocking film 10 permits a display 2 to beviewed from one or more directions and prevents the interference ofunwanted images. As seen in FIG. 4, a conferee can view the reflectionfrom the display 2 on a beamsplitter 6. The conferee cannot, however,see the display 2 emitted directly, because direct light is blocked bythe image blocking film 10. The conferee's attention, as a result, isnow focused solely on the reflection and not distracted by a view directfrom the display 2. A camera 4 in this arrangement is advantageouslymounted behind the beamsplitter 6 away from the conferee's work space.

FIG. 5 illustrates the use of the image blocking film 10 to block theimage when viewed from a side of the display 2. The image blocking film10 that makes the present invention possible is a material that exhibitsthe uncommon property of being selectively transparent depending on anangle at which the material is viewed. That is, when the gaze of anobserver is normal to a surface of the image blocking film 10, the filmappears to be totally transparent and any object on the opposite side ofthe film, such as the display 2, is readily visible. However, if theobserver views the image blocking film 10 at an angle to the film'ssurface, the image blocking film 10 has an appearance ranging fromopaque to translucent: the observer's view of any object on the oppositeside of the image blocking film 10 is obscured. The image can be blockedfrom two, three, or all four sides, if desired. For the presentinvention, it is critical that the image blocking film 10 block theimage from at least the angle from which the conferee is viewing thedisplay reflection, so that the display viewing surface itself isconcealed from direct view. An advantage to placing the image blockingfilm 10 on the right and left sides of display 2 is that the image willbe blocked from the reflection on the beamsplitter 6 when the display 2is viewed at an angle from either side. This feature adds security andprivacy to a teleconference which proves useful in a busy office area,since a passersby cannot easily view the image.

The image blocking film 10 is available from several sources and can bebased on various technologies. Whether the film is plastic or glass, theimage blocking film as it is presented here is a material that permitstransmission of light from at least one direction and reduces oreliminates light transmission from at least one other direction.Eyesaver International Inc. has an image blocking film named "PrivateEye" that diffuses light from various directions. From the perspectiveof the conferee, when using this film, light directly from the display(as opposed to the reflected image) appears milky and diffused,eliminating the focused image. The diffused light, even though visibleto the conferee, adequately conceals the image. Another image blockingfilm 10 is made by 3M Inc. and named "Light Control Film" and ispreferred, because it can eliminate virtually all light transmissionfrom a desired angle. This particular image blocking film 10 containsclosely spaced black microlouvers and a wide selection of louver anglesare available, and even more options are available by layering films.This means that the precise angle at which the image blocking film 10"shuts off" can be selected in advance. When the image blocking film 10"shuts off, " it ceases to transmit light so that if the observer viewsthe image blocking film 10 from an angle greater than the "shut off"angle the film appears to be opaque. When using this film the confereesees only the black surface of the microlouvers which entirely concealsthe image from the display 2 when viewed from the position of theconferee. The same effect can be produced by an array of tinymicrolouvers supported, for example, by their ends. In that case theimage blocker would not actually be a "film" but would fall within thebounds of the present invention.

This arrangement is preferably used with a flat panel display such as anactive matrix liquid crystal or plasma display, among others. Flatpanels permit the size of the terminal to be reduced and offersaesthetic design opportunities not possible with other eye contactdisplay systems. Of course, more bulky displays such as CRT displays andrear projection screen displays may also be used with the presentinvention. The added size of the terminal caused by bulky displays maynot be a disadvantage in some circumstances. Also, a bulky display canbe hidden by being built into a table with the screen surface flush withthe table surface, giving the appearance that the entire terminalconsists of a floating beamsplitter. Both flat panels and more bulkydisplays can be built into tables and into cabinets mounted sideways andeven upside down. In each configuration, image blocking film 10 isapplied to the display, blocking its image from the conferee's directview and leaving only the reflection on the beamsplitter 6 in view.Custom applications of this invention will be apparent to one ofordinary skill in the art.

FIG. 6 illustrates the present invention configured as a flat panelself-contained unit. The display 2 rests on a surface, such as a desk orcomputer. On top of the display viewing surface is the image blockingfilm 10 that functions in the manner previously described. Thebeamsplitter 6 is attached to the display 2 by hinges 14. The hinges 14permit adjustment of the beamsplitter 6 in relation to the display 2.Although 45 degrees is the "critical angle" for setting the beamsplitter6 relative to the display 2, positions between about 30 and 60 degreesare useful depending on the exact setup employed. A flexible rod 26holds the camera 4 in place and also carries electronic signal wires tothe display 2 which contains all electronic circuitry for the displayand the camera 4. The flexible rod 20 is attached to the display 2 by aconnector 22. The flexible rod 20 is one of many possible mechanismsthat can position the camera 4 behind the beamsplitter 6. Its advantageis that it can be bent into numerous positions, allowing the camera tobe adjusted both vertically and horizontally. A power line 16 suppliescurrent to both the display 2 and the camera 4. A first port 18 allowsthe camera image to be cabled to the teleconferencing equipment so thatthe captured image may be viewed on a distant terminal. A second port 19receives the incoming image signal, so that the distant conferee may beimaged on the display 2.

FIG. 7 illustrates a self-contained unit as seen in FIG. 6, except thatthe display 2 is mounted above the beamsplitter 6 with the displayviewing surface aimed downward into the reflection of the beamsplitter6. In this configuration the display 2 is connected to and supported bythe one end of the beamsplitter 6 and two support legs 24 that rest onthe desktop, computer, or other flat surface. This configuration'soperation is identical to the configuration of FIG. 6, except that nomeans of adjusting the beamsplitter 6 in relation to the display 2 isprovided.

The present invention may also be built into devices that have otherfunctions besides image display and image capturing. An example of thisis seen in FIG. 8, where the present invention is built as a part of alaptop computer 26 with a keyboard 28. In this configuration, thebeamsplitter 6 folds down onto the image blocking film 10 with thebuilt-in display underneath and integral with the laptop computer 26.The beamsplitter 6 has a latch hook 25 connected to it, which isreceived in a latch hole 27 when the beamsplitter 6 is folded down byhinges 14. The flexible rod 20 and camera 4 retracts into a slot (notshown) in the back when the device is not in use. Besides integratingthe present invention into a laptop computer, it may, in addition, bebuilt into numerous portable devices such as palmtops, personal digitalassistants, teleconferencing camcorders, and wireless teleconferencingsystems. Nonportable devices, as well, such as videophones, all-in-onehome computers, and televisions, to name only a few, will benefit fromthe present invention.

FIG. 9 illustrates a configuration where the main parts of the currentinvention can be configured as a separate kit to be added by theconsumer to upgrade the existing display 2 and provide the practicalityof modularity with interchangeable elements. As illustrated, the kitwould contain the image blocking film 10 which is placed on top of theviewing surface of the display 2 secured by a VELCRO™ hook-in-loopfastener (not shown), or other appropriate fastening means can be used.The beamsplitter 6 used in the kit is free-standing and held in place bystand legs 32 which are attached to the beamsplitter 6 by screws 34. Thekit is completed by the camera 4 which is connected to the flexible rod20 which, in turn, is connected to a flexible rod base 30.

Those skilled in the art will appreciate the design options madepossible by the present invention. For example, the display 2 can bemounted flush with a desk surface with the image blocking film 10seamlessly part of the desk's surface. From the conferee's perspective,the entire terminal would appear to consist of only the beamsplitter 6and the camera 4. Also, the display 2 can be built into decorativehousings and cabinetry and mounted aiming downward or sideways towardsthe beamsplitter 6. It is also conceivable that the image blocking film10 can be manufactured in designer colors.

Although desktop conferencing terminals will greatly benefit from thisinvention, it may also be configured into big screen displays. Theselarger displays are important when several conferees are imaged on onedisplay. The ergonomics of a life-size image of the conferees greatlyimproves the teleconferencing experience.

Those in the optical coating art will understand the vast variationspossible for the beamsplitter 6 in regards to its substrate, coating,and manufactured process. Both plastic and glass substrates, as well asstretched mylar, have been used for the beamsplitter 6. The beamsplitter6 can comprise a custom blend of optical coatings on a transparentsubstrate for superior reflectivity and transmission all the way down tooff-the-shelf one-way mirrors with inconsistent and poor opticalqualities. Also, the reflectivity and transmission, as well as otheroptical qualities of the beamsplitter 6, can be adjusted as needed.Despite these vast variations in the beamsplitter 6, the property ofbeing both reflective and transparent remains the single most importantconstant.

The following description details the construction of one embodiment ofthis invention. A frame and stand for the beamsplitter 6 was constructedfrom acrylic plastic on which the beamsplitter 6 was mounted at about 40degrees, so that the image is aimed slightly upward toward the face ofthe conferee. The beamsplitter 6 comprises a titanium coating on a floatglass substrate. The coating was optically designed for approximately40% reflectivity and 60% transmission. The plastic support frame wasdesigned to straddle a Shard active matrix LCD panel Model QA-1750BLlying flat on a table top. The image blocking film 10 used was 3M LightControl Film (type LCF ABRO O OB90 CLR GLS 030) and was positioned onthe viewing surface of the active matrix display, so that the image ofthe display is blocked from the conferee's direct view. Behind thebeamsplitter 6 am ELMO CCD miniature camera Model TSN 402 was attachedto a custom flexible rod 20 and base 30. The terminal was arranged asseen in FIG. 9 and was operated on a compressed video (MPEG)teleconferencing system.

Depending upon the angle between the beamsplitter 6 and the display 2,the reflection of the display 2 may have a trapezoidal shape. Thissubtle distortion is normally not a significant problem for mostobservers. However, if this distortion is unwanted, well-known imagemanipulation techniques can be used to "predistort" the image on thedisplay 2 into a trapezoid with its longer side in a reversed positionfrom a longer side of the trapezoid caused by the beamsplitter 6 angle.This way distortion caused by reflection will cancel out distortionimposed by image manipulation, and the reflected image will appearrectangular in shape. Also, manual controls may be provided for theconferee to choose the degree of predistortion so that the reflectedimage can be corrected at any angular setting of the beamsplitter 6. Anautomatic system can also be provided to simplify this procedure bysensing the angular relation of the beamsplitter 6 to the display 2 andautomatically applying the optimum amount of predistortion to the image.Since a bezel or outer edge of the display 2 may also appear in thereflected image, it may be necessary to either provide a trapezoidalbezel or make the bezel matte black so it is not apparent in thereflection. It may also prove advantageous to manufacture display panelsin a trapezoidal shape.

The reflection in beamsplitter 6 can also reflect not only the display1, but also the surface on which the display 2 rests or is mounted, suchas a desk top. If this reflection becomes an annoyance, alight-absorbing mat (not shown) extended around the display eliminatesthese unwanted reflections. Another method to eliminate these unwantedreflections is to put light-absorbing sides extended between the display2 sides and the beamsplitter 6.

For greater flexibility in orienting the display 2 to the beamsplitter6, the display 2 itself may be raised or lowered from the front or rearof the display 2. In FIG. 10 adjustable extension legs 36 are connectedwith stiff pivot hinges 38. The display 2 with these extension legs 36can be raised and lowered from both the front and the rear. For evengreater flexibility in positioning the beamsplitter 6 in relation to thedisplay 2, one can allow the beamsplitter 6 to be adjusted by tilting,moving backwards and forwards, and closer and further from the display2. Extension arms 42 and 40 provide all of these movements through theuse of connected stiff pivot hinges 44, 46, and 48. The conferee canadjust tilt, up and down and back and forth, with this positioningmechanism. Other positioning mechanisms, as well, may be integratedaccording to the needs of the particular configuration.

An additional amenity that can improve a free-standing eye contactterminal employing the present invention is the addition of a simpleturntable beneath the unit. The turntable allows the entire unit toswivel to face the conferee. This is especially useful in the case ofgroup teleconferences where a number of individuals want direct"one-on-one" contact with a person at a remote terminal. The turntableallows the display 2 and the camera 6 to be instantly aimed towards anyparticipant. This can be accomplished either manually or automatically.The image blocking film 10 is selected so that no one in the group candirectly view the display 2. That is, two layers of image blocking film10 are used so that the image is blocked from all viewing angles exceptfor a line of sight normal to the surface of the display 2.

To enhance the apparent reflectivity of the beamsplitter 6, ambientlight behind the beamsplitter 6 may be reduced, depending upon theoptical properties of the beamsplitter 6 and the intensity of theambient light. FIG. 12 illustrates the use of an opaque material 50(such as black painted plastic) covering all of a rear surface of thebeamsplitter 6 except for a small area through which the camera 4 isaimed. Ambient light is completely eliminated from behind thebeamsplitter 6 and, thereby, substantially improves the apparentreflectivity of many types of the beamsplitter 6. An optional camerahousing 52 may be built of light absorbing material, as well. If onlyambient light from a specific direction need be eliminated, then imageblocking film 10 can be applied to the back side of beamsplitter 6 asseen in FIG. 13. Other ambient light reduction methods may be used, suchas mounting the present invention in an enclosed cabinet or providing aremovable hood for the terminal.

Because the beamsplitter 6 is mounted at an angle toward the conferee itis possible to bounce sound off the beamsplitter 6. By doing soteleconferencing audio is greatly improved, because sound will seem tooriginate from the center of the beamsplitter 6 where the image of thedistant conferee's mouth is located. FIG. 14 illustrates a speaker 55aimed toward the beamsplitter 6 so that sound is bounced toward theconferee. Special directional speakers may be used to enhance thiseffect. The speaker 55 can also be mounted on the side of the display 2(not shown) and additional speakers 55 may be used in various placementsaround the display 2.

An additional embodiment of the present invention employs a bowedbeamsplitter 56 of FIG. 15. This enables the display 2 to be configuredmore narrowly than the common aspect ratio display 2. By squeezing thevisible image with well-known image manipulation techniques, thissmaller compressed image can be expanded to a larger image whenreflected onto the bowed beamsplitter 56. This configuration isespecially useful when a large image is desired, but the desk surfacewhich the display rests on is limited in area.

Antireflective coatings can be applied as needed to suppress unwantedreflections from any of the optical surfaces involved. On the back sideof the beamsplitter 6, opposite the reflection side, an antireflectioncoating can serve to eliminate the ghosting effect apparent with manytypes of beamsplitters. Also, an antireflective coating, substrate, filmtextures (i.e., matte finish), light-absorbing color, or similarfunctioning material can be applied on top of or as a part of the imageblocking film 10 when it is necessary to reduce a "back reflection,"which is an image reflected from the beamsplitter 6 back onto the imageblocking film 10. FIG. 16 shows another method of dealing with backreflections. When the image blocking film 10 is angled (as opposed toparallel) in relation to the display 2, the back reflections arediminished or eliminated. An angle between the image blocking film 10and the display can range from a few degrees to a much as 30 degrees ormore. At large angles the image blocking film 10 advantageouslyincorporate slanted microlouvers to compensate for a change in angularrelationship between the conferee and the image blocking film 10.

Another embodiment of the image blocking film 10 used forteleconferencing eye contact is seen in FIG. 17. The image blocking film10 has significantly improved the prior art beamsplitter 6 arrangement,as seen in FIG. 2. Prior art technology based on polarizerssignificantly reduces the brightness of the display 2 since polarizersabsorb at least half of the incident light. This, combined with thefurther brightness reduction caused by the beamsplitter 6, creates anoticeably dim image. The image blocking film 10 has a highertransmissivity than the polarizer 9, allowing a far brighter image.Also, a single substrate image blocking film 10 applied between thedisplay 2 and the beamsplitter 6 does not suffer from the complexity ofaligning the two polarizers 9 and 11. The image blocking film 10 allowsthe conferee to look through a single substrate to the display 2 imagebehind. From the perspective of the camera 4 the image is concealed bythe image blocking film 10. Because the image is blocked, the camera 4can be aimed more directly toward the display 2, i.e. between about 20degrees and about 40 degrees, without picking up the light of thedisplay 2 passing through the beamsplitter 6. As a result, thebeamsplitter 6 can be angled more closely to the display 2, therebyreducing the protrusion of the beamsplitter 6. FIG. 17 shows the imageblocking film 10 parallel to the front surface of the display 2. Theimage blocking film 10 may also be located on the side of thebeamsplitter 6 facing the display 2 or at any position between.

Although this terminal still suffers from a protruding camera 4 on thestand 12, this protrusion can be reduced somewhat by using a small microvideo camera. Instead of the stand 12, the camera 4 can be mounted on amovable base (not shown) which rests directly on the table or desksurface. A second mirror (not shown) may be used near the camera tocorrect the image reversal caused by the reflection of the beamsplitter6. The hood 8 is an optional element and may be used if ambient light isexcessive. Variations in terminal design made possible by this improvedbeamsplitter 6 arrangement will be apparent to those skilled in the artof teleconferencing ergonomics.

Depending upon the type of the beamsplitter 6 and the degree oftransmissivity used, adjustments to the light sensitivity of the camera4 may improve image quality. Also, adjustments to the brightness of thedisplay 2 may improve the reflectivity of some types of beamsplitters.Such light sensitivity and brightness adjustments of camera 4 anddisplay 2 will be apparent procedures to one of ordinary skill in theart.

As is the case with all eye contact terminal technology, true eyecontact cannot occur between conferees unless both conferees have an eyecontact terminal. Even if only one conferee has an eye contact terminal,however, that conferee can transmit a eye contact signal for at leastthe other conferee to enjoy. In a multiple conferee session, portions ofthe screen can be designated for simultaneously displaying severalincoming conferees. A more complex approach to multiple conferees is touse multiple cameras side by side in order to transmit different pointsof view of the conferees as if sitting around a table. Although notshown, it will be apparent as to how side-by-side cameras would beconfigured behind the beamsplitter 6.

Because the display is reflected on the beamsplitter 6, the image willappear to the conferee to be reversed. Image reversal techniques (eitherphysical such as a mirror or electronic) can easily remedy this problemby appropriately reversing the image before it is displayed so that,when reflected on the beamsplitter, the image will assume its correctviewing orientation.

When viewing the reflection of the display 2 from the sides, thereflection of the display 2 will fall off the edge of the beamsplitter 6when the beamsplitter 6 is the same size as the display 2. A simpleremedy for this is to make the beamsplitter 6 as wide as necessary, sothat the entire image remains reflected even when viewing from thesides.

Various mechanisms have been explored for camera positioning and cameraaiming. Motorized positioning and aiming systems have been developed toallow remote control of the camera. Also, autotracking systems permitthe camera to follow the conferee as he or she moves about. The camera 4can also be attached directly to the beamsplitter 6. When mounting thecamera 4 to the beamsplitter 6 as seen in FIG. 12, the camera 4 aimingdirection can operate independent of the positioning of the beamsplitter6 such as in FIG. 11. Camera 4 can also be mounted in a position notdirectly behind the beamsplitter 6. In such a case mirrors or an imageconduit can redirect the image passing through the beamsplitter 6 to thecamera 4.

Additional teleconferencing components may be included as desired interminals configured with the present invention. The camera 4 can beconfigured as a small detachable camcorder and thereby add the economyof serving multiple purposes. The camera 4 may, as well, be configuredwith remote controls. Lights can also be added as desired to enhanceimage capture quality. Lights may also be placed behind the beamsplitter6 so long as they do not interfere with the display 2 image reflection.Microphones can be integrated into various terminal configurations withthe present invention. Like the speakers 55 the microphones canadvantageously aimed so that sound bounces off the beamsplitter 6. Theaddition of optical coatings, such as CRT radiation reduction filters,color filters and contrasts, and glare guard technologies, may be addedas well. Also, 3-D displays and fresnel lenses that expand the size ofthe display image will readily integrate with this invention. Othermodifications will be apparent as new teleconferencing, video camera,computer, and display technology transforms during this time of globaltelecommunication transition.

Of course, the teleconferencing terminal used as part of the currentinvention can be, and preferably is, a multipurpose personal computerrunning a graphical interface program such as Windows 95®. Therefore,the graphical interface can be used to place calls, select views, etc.That is, if a conference call is undertaken between several conferees,the various conferees can be displayed in separate windows on thescreen. One particular conferee can be selected to occupy the entiredisplay 2 by choosing the conferee's window using a keyboard, a mouse, atouch screen, or similar user input means.

Those skilled in the art will appreciate that various adaptations andmodifications of the just-described preferred embodiment can beconfigured without departing from the scope and spirit of the invention.Therefore, it is to be understood that, within the scope of the appendedclaims, the invention may be practiced other than as specificallydescribed herein.

What is claimed is:
 1. A kit for use with an image display to provide animproved eye contact teleconferencing terminal for allowing a firstconferee to maintain eye contact with an image of a second confereeimaged by the image display, the kit comprising:a semireflectivetransparent panel and means for positioning the semireflectivetransparent panel to form an angle of between about 30 and 60 degreeswith the image display thereby defining a first surface of thesemireflective transparent panel which faces the image display and asecond surface of the semireflective transparent panel which faces awayfrom the image display; a video camera and mounting means for holdingthe video camera disposed on a side of the semitransparent panelopposite the image display to capture an image of the first confereethrough the second surface of the semireflective transparent panel; anda layer of image blocking film disposed between a front surface of theimage display and the semireflective transparent panel allowing theimage of the second conferee to pass through and reflect from thesemireflective panel while blocking a direct view of the image displayfrom the first conferee.
 2. The kit of claim 1, wherein the side of thesemireflective transparent panel opposite the image display is enclosedin opaque material to improve a quality of the reflection on thesemireflective transparent panel by shielding the second surface of thesemireflective transparent panel from ambient light.
 3. The kit of claim1, wherein image blocking film is applied to the second surface of thesemireflective transparent panel to improve a quality of the reflectionon the semireflective transparent panel by shielding the second surfaceof the semireflective transparent panel from ambient light.
 4. Theteleconferencing terminal of claim 1, wherein the semireflectivetransparent panel is bowed to optically expand a compressed image on theimage display, thereby elongating the reflection on the semireflectivetransparent panel.
 5. The teleconferencing terminal of claim 1 furthercomprising a means for reproducing sound disposed in proximity to theimage display with a direction of sound propagation directed towards thesemireflective transparent panel for reflecting sound from said panel sothat the first conferee perceives the sound as issuing from the imagereflected by the semireflective transparent panel.
 6. An improved eyecontact teleconferencing terminal for allowing a first conferee tomaintain eye contact with a second conferee imaged by theteleconferencing terminal, the teleconferencing terminal comprising:asubstantially planar image display for producing an image of the secondconferee; a semireflective transparent panel forming an angle of betweenabout 30 and 60 degrees with the image display thereby defining a firstsurface of the semireflective transparent panel which faces the imagedisplay and a second surface of the semireflective transparent panelwhich faces away from the image display; a video camera disposed on aside of the semireflective transparent panel opposite the image display,the video camera capturing an image of the first conferee through thesecond surface of the semireflective transparent panel an image of thefirst conferee who is disposed on the image display-side of; and a layerof image blocking film disposed between a front surface of the imagedisplay and the semireflective transparent panel allowing the image ofthe second conferee to pass through and reflect from the semireflectivepanel while blocking a direct view of the image display from the firstconferee.
 7. The teleconferencing terminal of claim 4, wherein the sideof the semireflective transparent panel opposite the image display isenclosed in opaque material to improve a quality of the reflection onthe semireflective transparent panel by shielding the second surface ofthe semireflective transparent panel from ambient light.
 8. Theteleconferencing terminal of claim 6, wherein image blocking film isapplied to the second surface of the semireflective transparent panel toimprove a quality of the reflection on the semireflective transparentpanel by shielding the second surface of the semireflective transparentpanel from ambient light.
 9. The teleconferencing terminal of claim 6,wherein the semireflective transparent panel is bowed to opticallyexpand a compressed image on the image display, thereby elongating thereflection of the image display.
 10. The teleconferencing terminal ofclaim 6 further comprising a means for reproducing sound disposed inproximity to the image display with a direction of sound propagationdirected towards the semireflective transparent panel for reflectingsound from said panel so that the first conferee perceives the sound asissuing directly from the image reflected by the semireflectivetransparent panel.
 11. An improved eye contact teleconferencing terminalfor allowing a first conferee to maintain eye contact with a secondconferee imaged by the teleconferencing terminal, the teleconferencingterminal comprising:a substantially planar image display; asemireflective transparent panel forming an angle of between about 30and 60 degrees with the image display; a video camera disposed oppositethe image display on a first side of the semireflective transparentpanel, the video camera capturing, through the semireflectivetransparent panel, an image of the first conferee who is disposed on asecond side of the semireflective transparent panel; and an imageblocking layer comprised of micro-louvers disposed between a frontsurface of the image display and the semireflective transparent panelallowing the image of the second conferee to pass through and reflectfrom the semireflective panel while blocking a direct view of the imagedisplay from the first conferee.
 12. The teleconferencing terminal ofclaim 11, wherein means are provided for altering an angularrelationship between the semireflective transparent panel and the imagedisplay.